1. Field
The present invention relates to an information processing system, an information processing apparatus, and an information processing method which use a video terminal conversion adaptor.
2. Description of the Related Art
Conventionally, various techniques for controlling, according to the manner of use of a user, a video signal that is generated by a information processing apparatus such as a personal computer have been proposed (refer to JP-A-2007-179225 and “VESA DisplayPort Interoperability Guideline Version 1.1”, edited by Video Electronics Standards Association (VESA), Jan. 28, 2008, for example).
The information processing apparatus disclosed in JP-A-2007-179225 is configured so as to be able to use plural graphics chips and processes a video signal using an optimum graphics chip according to the use of the user.
The document “VESA DisplayPort Interoperability Guideline Version 1.1” has a disclosure as to a video terminal conversion adaptor (hereinafter referred to as a conversion adaptor) for connecting video terminals that comply with different standards. In particular, it describes specifications that are recommended for an adaptor for a DisplayPort (hereinafter abbreviated as DP) terminal and an HDMI (high-definition multimedia interface) terminal and an adaptor for a DP terminal and a DVI (digital visual interface) terminal. The conversion adaptors disclosed in this Non-patent document make it possible to easily connect an information processing apparatus having a DP terminal as a video output terminal to an information processing apparatus having an HDMI terminal or a DVI terminal as a video input terminal.
The DP signal is different from the HDMI signal and the DVI signal in bias voltage (physical layer information). To adjust the difference in bias voltage, the conversion adaptors disclosed in the document “VESA DisplayPort Interoperability Guideline Version 1.1” is equipped, in themselves, with an integrated circuit (level shift IC) for adjusting a voltage. ICs are smaller in signal variation and are less affected by variations in performance of components than circuits that are combinations of discrete components. Conversion adaptors incorporating this type of IC can accommodate differences between individual information processing apparatus through control by the IC and hence are high in versatility.
However, in the conversion adaptors disclosed in the document “VESA DisplayPort Interoperability Guideline Version 1.1”, no consideration is given to a case that the internal configuration of an information processing apparatus is known. Where the internal configuration of an information processing apparatus is known, the use of this kind of IC only for voltage adjustment is too redundant.